1. Field of Invention:
The present invention relates to seismic surveying, namely marine walkaway vertical seismic profiling.
2. Description of Prior Art:
Walkaway vertical seismic profiling, or walkaway VSP, is a known technique of seismic surveying. It involves taking seismic data readings with a hydrophone at each one of various depths in a well borehole as a seismic source emits seismic waves at a number of shot-points along a seismic line of profile. Although the data obtained were useful, the technique has not been widely used. It could only be performed at locations where a well borehole had already been drilled. Additionally, VSP data acquisition was expensive since it required the seismic source be moved to each shot point along the entire line of profile several times to emit waves, once for each different hydrophone depth of interest in the well borehole.